Yii dropdown with AJAX not working as expected - php

Question

I have the following view named 'findreseller.php':
<?php
$countries = CHtml::listData(Country::model()->findAll(), 'id', 'name');
echo CHtml::dropdownlist('find_reseller', '', $countries,
array('ajax'=>array(
'type'=>'POST',
'url'=>Yii::app()->getController()->createAbsoluteUrl('/webcare/reseller/loadAjaxData'),
'update' =>'#data',
)
)
);
?>
<div id="data">
<?php $this->renderPartial('_ajaxContent', array('dataProvider'=>$dataProvider))?>
</div>
_ajaxContent just echoes the result, nothing special there...
The dropdown, as you can see is generated with CHtml because I dont't need a form. I just need an onChange event to do something...
As per the code that follows, in '/webcare/reseller/loadAjaxData' I have:
public function actionLoadAjaxData() {
$country = $_POST['find_reseller'];
//do something...
$dataProvider=new CArrayDataProvider($country_reseller);
$this->render('findreseller', array('dataProvider' => $dataProvider));
}
I can tell that I am missing something, but I am not sure what exactly.
Edit
Modified like this:
<?php
//CHtml::form();
$countries = CHtml::listData(Country::model()->findAll(), 'id', 'name');
echo CHtml::dropdownlist('find_reseller', '', $countries,
array(
'ajax' => array(
'type'=>'POST', //request type
'url'=>CController::createUrl('/webcare/reseller/loadAjaxData'), //url to call.
//Style: CController::createUrl('currentController/methodToCall')
'update'=>'#city_id', //selector to update
'data'=>'js: $(this).val()',
//leave out the data key to pass all form values through
)
)
);
//empty since it will be filled by the other dropdown
echo CHtml::dropDownList('city_id','', array());
//CHtml::endForm();
?>
<div id="data">
<?php $this->renderPartial('_ajaxContent', array('dataProvider'=>$dataProvider))?>
</div>
And now I get:
http://prntscr.com/42wwx6
And I have the following controller action:
public function actionLoadAjaxData() {
$country = $_POST['country_id'];
...
$dataProvider=new CArrayDataProvider($country_reseller);
$data = User::model()->findAll('country_id=:country_id AND reseller=:reseller',
array(':country_id'=>(int) $_POST['country_id'], ':reseller'=>1));
$data=CHtml::listData($data,'city','city');
foreach($data as $value=>$name)
{
echo CHtml::tag('option',
array('value'=>$value),CHtml::encode($name),true);
}
$this->render('action_name', array('dataProvider' => $dataProvider));
}
Edit 2
If I write a die in actionLoadAjaxData(), right at the beginning, the method is loaded fine, the action is ok and the server answers 200.